terry, that would definitely create a weight & balance problem. as a rotary wing aviator myself, i can appreciate that issue. with that said, if he were to upgrade to, let's say, an sr20det, that may do the trick.
for reliability, yes you do need a powerplant that runs for a long time under load. however, there is [as you may guess] a feature that helicopters have which allows them to 'coast' when there is a power interruption-just like a bicycle that allows you to coast when not pedaling.
as the pilot i can tell you that when the big fan slows, the cockpit becomes...a bit warm. then she begins to fall, quite rapidly. i've performed many of these maneuvers, called autorotations, but all were for training, not actual engine failures. actually not too complex and end in a relatively safe and 'soft' landing.